U2 are a rock band formed in Dublin, Ireland. The band consists of Bono (vocals and guitar), The Edge (guitar, keyboards, and vocals), Adam Clayton (bass guitar), and Larry Mullen, Jr. (drums and percussion).
The band formed in 1976 when the members were teenagers with limited musical proficiency. By the mid-1980s, the band had become a top international act. Their success as a live act was greater than their success as a record selling act until their 1987 album The Joshua Tree, which, according to Rolling Stone, elevated the band's stature "from heroes to superstars". U2 responded to the dance and alternative rock revolutions and their own sense of musical stagnation by reinventing themselves with their 1991 album Achtung Baby and the accompanying Zoo TV Tour. Since 2000, U2 have pursued a more conventional rock sound that retains the influence of their previous musical explorations.
U2 have sold more than 145 million albums worldwide and have won 22 Grammy Awards, more than any other band. In 2005, the band were inducted into the Rock and Roll Hall of Fame in their first year of eligibility. Rolling Stone magazine listed U2 at #22 in its list of the 100 greatest artists of all time. Throughout their career, as a band and as individuals, they have campaigned for human rights and social justice causes, including Amnesty International, the ONE Campaign and Bono's DATA (Debt, AIDS, Trade in Africa) campaign. source: wikipedia